Why Was Christopher Columbus Wrong

Christopher Columbus didn’t actually prove that the Earth itself was round. The reason is that because, the time when he traveled across the Atlantic ocean, or sailed to the ocean, there were quite few people who actually thought that it is actually possible to fall thought the edge of the Earth. The myths itself mentioned that the people said there were monsters and boiling water and it is impossible to cross over it, and yet no one did it except for Christopher Columbus.
Offensive: Christopher Columbus and the rest of his crew were the reasons of the spreading of diseases, and were introduced syphilis and smallpox to most of the population that were completely devastated by them. Yet, I still thought that this day should turn into Native